Electrochemical sensors are used for the quantification of components or analytes in a sample of liquid such as blood or urine. Sensors of this type are disclosed in U.S. Pat. Nos. 5,958,199 and 5,798,031. These sensors include an insulating base with carbon electrodes printed on the base. The electrodes are covered with a reagent and are located in a capillary channel. The capillary channel is defined by a spacer positioned between the base and a cover piece.
Other electrochemical sensors have two parts, a base and a lid. The lid forms three sides of a capillary space and the base forms the fourth. The base and lid are laminated together to form the sensor.
Sensors of this type are used by dipping an open end of the capillary channel into test liquid. The liquid is drawn by capillary action into the capillary channel to cover a reagent and/or enzyme in the capillary channel near one or more electrodes. A measurement of an analyte in the test liquid can then be made. The usual way to fabricate sensors of this type is to precision screen print active areas within a capillary area formed by a shaped top lid. It is desirable to reduce the cost and assembly required by this construction. Moreover, it is difficult to provide electrodes in a small molded capillary channel of less than 0.005 inches in height and it is desirable to provide a sensor of this size with molded electrodes so that such a sensor could be used for electrochemical analysis.